I can't be 100% sure but most likely A26x0 is always first autoconfig board.

btw, does anyone have A2620/2630 pre-v6 ROM? ROM versions that are not 512k KS ROM compatible. Only v6 and v7 seems to be available.

A2620/30 RAM would have had to be the first board, otherwise it wouldn't be used until the user fills up all other (much slower) Zorro II RAM. [I guess board configuration order from first to last is CPU slot, then the rightmost Zorro II slot (closest to CPU slot) to the leftmost.]

I don't know where to get earlier 2620/30 ROM versions either. Maybe someone with the actual hardware will read this thread and offer to dump them??? Based on old Usenet postings, at least -02 and -04 versions were released publically. An old Usenet thread (started by Holger Kruse, who went on to write ReOrg and the Miami TCP/IP software) mentions a company in Germany producing their own replacement for it:

Code:

The German computer magazine "Amiga Special Extra" reports in its
2/91 edition, that there is an incompatibility between Kickstart 2.0
and the A2630.
The reason is that both Kickstart 2.0 and the A2630 Rom-Bios start
at the same physical address $f80000.
[... stuff deleted...]
The computer magazine also reports about a company in Oldenburg, Germany
who sell a new A2630 bios version that is located at address $f70000 and
also contains an improved boot menu.

Talking of the 2620/30 ROM... if you get into the monitor (keep holding down right mouse button to bring up menu, then press shift-M) you can run various commands. Type ? for a list. i lists autoconfig devices and memory. With my test config (A2630 ROM v7, 4MB A2630 memory, 2MB A2091) the output looks like this:

Notice the bogus total memory figure and memory at 01000000. And the line for chip memory says 00000000-00100000 regardless of the actual amount of chip RAM (it's the same for 512KB and 2MB chip). I wonder whether that happens on real hardware.